Fractionation of mixtures of fatty oils and free acids derived therefrom



June 1, 1943. J. D. JENKINS FRAGTIONATION OF MIXTURES OF FATTY OILS AND FREE ACIDS DERIVED THEREFROM Filed May 13, 1940 vk mGDSm. n@

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Jou/v 0. dawn/N6 Patented June l, i943 imitan l sm TENT OFFICE FRACTIONATION F MIXTURES OF FATTY OILS AND FREE ACIDS DERIVED THERE- FROM Application May 13, 1940, Serial No. 335,007

The present invention relates to processes of fractionating glycerides of the higher fatty acids and to the fractionating of mixtures of free acids derived from such glycerides, and it has particular relation to the fractionation of such compounds by selective liquid phase extraction with a polar solvent which has a higher degree of solvency for certain components of the mixture than for others.

One object of the invention is to provide a process of the foregoing type which can be conducted at a substantially higher temperature than is permissible by other processes, which is less subject to temperature fluctuations than processes heretofore available and which can be operated without danger of solidiflcation of low melting point materials.

A second object of the 'invention is to provide a process which permits of a relatively high output for a given amount of apparatus.

A third object of the invention is to obviate the necessity of dehydrating the solvent in order to remove the accumulations of water from the material extracted.

A fourth object of the invention is to reduce the amount of solvent required in making extractions in the foregoing process.

It is recognized that most of the animal and vegetable oils comprise mixtures of glycerides of various fatty acids. Among the oils of this type may be included linseed oil, soya bean oil, perilla oil, marine oils, such as sardine, menhaden, cod, halibut and whale, cottonseed oil, peanut oil, corn oil, sunower seed oil, olive oil, tallow, lard and the like. components of these oils diier from each other primarily in the degree of saturation or unsaturation or the position of the unsaturated valences .in the acid residues. However, certain other oils of the type of coconut oil, palm oil and the like comprise mixtures of glycerides, the components of which to some extent diier from each other by reason of variances in the degree or manner of unsaturation but probably to a greater degree differ by reason of differences in the chain length of the acid radicles or residues in the esters. Of course, the free fatty acids existing in or derivable from these oils differ from each other to a. substantial degree in the same manner as the glycerides from which they are derived.

In copending applications Serial Nos. 144,315, now issued as Patent 2,200,390, filed May 22,1937, and 251,340, no w issued as Patent No. 2,200,391, led January 17, 1939, both to Stephen E. Freeman are disclosed processes of separating glycerides of the foregoing types and the free fatty acids from such glycerides into fractions which are relatively enriched in certain components of the mixtures and correspondingly impoverished In most instances the glyceride in other components. These processes are based upon a preferential solvent action of organic polar solvents for the more highly unsaturated or more actively unsaturated components of the mixtures or for the components of shorter chain length. By reason of such process it is possible by the proper contacting of the oils of free acids with the solvents to obtain two liquid phases, one consisting essentially of raflinate oil or free fatty acid with a certain proportion of selective solvent dissolved therein and the other consisting mainly of solvent with a fraction of the material to be extracted in solution.

The more unsaturated material or actively unsaturated material, or material ofshorter chain length is to be found dissolved in the solvent, Whereas the more saturated materials and longer chain length materials remain out of solution, but to a certain extent become saturated with the solvent. According to the processes these liquid phases may be separated from each other by settling and decantation or by centrifugation and upon elimination of the solvent, for example, by distillation fractions of oils or free fatty acids therefrom are obtained, which differ for example by reason of iodine value or molecular weight. Upon application of such process to drying and semi-drying oils, it is possible to obtain fractions which are relatively highly unsaturated. as compared with the original oil and which esters possess substantially enhanced drying properties. Therefore, their value for use in paints, varnishes, and the like is increased. Simultaneously, of course, there is obtained a fraction which is of lower iodine value and which is particularly applicable for use in food products and other such uses where high iodine value is not required, or is objectionable. More completely saturated materials, such as cottonseed oil may also be fractionated to obtain fractions which are especially useful for foods and perhaps in some cases to obtain fractions to possess drying properties. These of course are merely examples of the application of the broad process of invention.

The present invention is based upon the discovery that the polar solvents as disclosed in the foregoing applications and other solvents of similar properties may in many casesbe incorporated with a second material, which at least to some degree is miscible in the solvent, but' is a non-solvent for the glycerides previously mentioned or the free fatty acids derivable therefrom, in order substantially to modify the prop erties of the solvent. In general where a nonsolvent for oil or free fatty acid, such as water, is employed in conjunction with the polar solvent, it is found that the temperature of miscibility with the oil or acid is substantially increased so that liquid phase extraction can be conducted at wise permissible. Also. in many cases where the polar solvent possesses a considerable degree of solubility for all components of the oil the selective action of the pure solvent is found to be so masked that fractionation of oils and free fatty acids into components cannot be effected. However, by the addition of a judicious amount of a non-solvent for the oil or acid, e. g. water, which, however, is soluble in the polar solvent, it is possible so to lower the general solubility of the oil or acid as to admit of separating the mixture into two liquid phases.

It,of course, will be apparent that the extraction must be so conducted that the solvent employed infthe process will exert a certain degree of solvency for the oil or the free acid to be extracted, and it, also, must be of polar nature or possess certain polar groups as disclosed in the foregoing applications, so that it will exert a preference for the more unsaturated or actively unsaturated components or the short chain length components of the mixtures to be treated. It must also possess at least some solubility with water. The following are examples of a series of organic polar vsolvents which are contemplated as being within the scope of the present invention:

Table A Hydroxy! Hydrocyl-Other Meth l alcohol Allyl alcohol Ethylyalcohol Ethylene chlorhydrin n-Propyl alcohol Glycerol monochlorhydrin iso-Propyl alcohol Beta, gamma-dibromo propyl Ethylene glycol alcohol Propylene glycol Beta-hydroxy gro ionitrle Glycerine Beta-ethoxy et y lactate Beta-ethoxy ethyl glycolate Hydrimll-Eskr Furi'ural alcohol 2-nitro-l-butonol Methyl glycolate Ethyl glycolate 74cm Beta-h droxy ethyl acetate Ethyl tate Forrnic acld Mono acetin Acetlc acid i Diat n- Eater-Carbonia! l-lycrozyt-Carbcmyl Methyl levi-Innate Meth Ibutanolone Eth llevulmate Acetymethyl carbinol Met l aoetoacetate Diaoetone alcohol Ethy acetoacetate Methyl acetyl lactatev Isopropyl acetoacetatc Eater Aldehyde Methyl fornat dif t Acetaldehyde orma e g yco Aldehude-Other gdlgfe Methoxy acetaldehyde Methyl mme lfgliltlrlbewideh de Ethyl oxalate Y Eater-@Mar Cafbmf/l Methyl cellosolve formate Afetonyl acetone Methyl cellosolve acetate Amine' Methyl cellosolve adipate Dimethyl cellosolve succinate methylene mamme Ethyl n-methyl carbamale Triethylene tetraminc Methyl chloroecetate Methyl cyanoacetate Nim'le A'mdes Propionitrile FOU-amide Eaters o incr anic acids Atamide f a Propionemide grintltslyllglgllgte tymm ne Bu de Beta-metgoxy ethyl carbonate Nitro Dmethyl Sulfate Nitromethane Nitroethane Hydrcrul-Ether Methyl 'cellosolve Cellosolve Diethylene glycol Triethylene glycol Farbitol 2-hydroxy-methyl-l,Ii-dioxolane All of the polar solvents above listed are capable within themselves of forming immiscible systems with various drying or semi-drying oils, such as soya bean oil, at a temperature above about 0 75 a substantially higher temperature than is other- C. However. if they are warmed the oil and the solvents become completely miscible, but 'upon cooling they will separate i'nto phases in the manner previously described. The proportion of oil remaining in the solventV will depend upon the temperature and may vary according to the requirements placed upon the fraction which is to be separated by extraction. a

The following constitutes a partial list of solvents which are miscible with glyceride oils at temperatures down to zero degrees, but which can be admixed with water in substantial amounts, in order to form systems immiscible with oils and acids.

' able proportion of water.

Isobutyric acid to; '.lllsisehgtvith free fatty acids and are not suitable In the operation of the process the free fatty acids or oils to be extracted may be merely vadmixed with the desired solvent containing a suit- If the admixture is effected at a temperature above that of miscibility of the acid-solvent mixture or if the mixture of incompletely miscible solvent and free fatty acids or oil is brought to a higher temperature,

itwill be apparent that the system will become completely miscible. However, upon cooling the system below the temperature of miscibility separation into phases will occur. One phase will consist of solvent saturated wtih extracted glycerides or fatty acids which are substantially enriched in one component of the said mixture. The other phase will comprise essentially the less soluble component of the mixture saturated with a certain amount 0f solvent.

Obviously as the completely miscible solution of free fatty material and solvent is cooled down. more and more of the acids in the extract phase will be thrown out and correspondingly the raf- `nate phase will be increased. As the size of the fraction in solution in the solvent is reduced by lowering of the temperature itis obvious that the fractionrstlll remaining in solution will be enriched in the more soluble components of the free fatty acids or oil. However, the yield of extracted acids or oil,l of course, is reduced. Therefore, in practicing the invention it is desirable merely to reduce the temperature until a fraction of desired proportions or of desired constituency is retained in the solvent. After separation of the mixture as distinct phases, th'e latter may be removed from each other, for example, by allowing them to settle into liquid layers and then decanting or otherwise removing the layers, or by centrifugating the mixtures of phasesin an appropriate apparatus.

In .general the separation ofV theliquid phases from each other will be effected at a temperature within a range of about 2 to 40 C.4 below that of complete miscibility of the solvent-fatty acid or oil mixture. The temperature of complete miscibility of any particular system of solvent and fatty acid is easily determinable by merely admixing samples of the oils or free fatty acids with wet solvent and Warming the resultant mixture until it becomes completely miscible. Subsequently the mixture may be cooled until it tends to separate into phases as evidenced by the formation of a haze or cloud.

The ratio oi wet solvent to oil may vary over a relatively wide range, for example, of 1 to 1, up to 10, or even more of solvent to 1 part of fatty acid or oil. 4

Soya bean oil was extracted with wet acetone, the ratio being 1 to 4. The results are tabulated as follows:

Water Water 3.1% 0.5%

Temp. of sepn C 27 0v Per cent extract 4l 57 Per cent ran. 59 43 I. V. ext 139. 6 139.0 I. V. raif. 132.8 131.5 I. V. orig. oil 136 136 drained oil'. 'I'he solvent in the two vfractions was removed by vacuum distillation. The results of the tests are tabulated as follows:

Wet furfural Linseed Soya Fish Temp. misc.,C

N'rE.-Linsced oil and soya bean oil were alkali rened.

'I'he eiect of water on increasing the temperature of miscibility of furfural on various oils is shown by the following table in which the temperatures of miscibility of the oils in wet and dry furfural are compared:

` Coconut Re Soy- Lin- -Pcrlined o bean seed illa fish seed #i #2 oil C. C. C'. (7. C'. T m misc. anhyd.. l 37 3l 3l 24 37 53 e get uA 95 84 70 6l) 70 84 96 In tem due to vcvaltgr. -l 44 47 39 29 46 47 43 Iodine Value oil 132 179 15 10 208 203 107 The effect oi varying the amounts of water on the temperature of miscibility of the various oils andfurfural isshown by the following table:

Fish Soy Cow- Percent water by vol. In lurf. ou bea Linseed nut 37 51.5 35. 5 2i) 46 59 44. 5 37 54 67 53 45 61 74 si 53 68 81 6I) 60. 5 75 88 76 68 8l 94 83 75 84 98. 5 90 8l 87 100. 5 95 88 90 99 92 96 In the preceding vtable oil and furfural were contacted in the ratio of 1 part of oil for each 5 parts of anhydrous furfural.

The wet solventsmay also be employed at appropriate temperature in the fractionation of free fatty acids of the foregoing oils or similar oils.

However, the rise in the miscibility temperature of the mixture is substantially less pronounced Anhydrous Wet furfural furfural 61 79 50. 5 68 141. 7 141. 0 m, o 12s. 2 135. 8 135. 8

65 'In 33 58 66. 3 1117. 4 |97. 6 19S. 0 |96. 5 196. 1 196. 1

f As previously indicated various processes and apparatuses may be employed in effecting the contact of the solvent and the oil or free fatty acid to be extracted. Th'e apparatus disclosed in the drawing constitutes anv example of one suitable form.

'I'he apparatus as disclosed includes an extraction tower or column I0 which `may be packed with Raschig rings or Berl saddles, etc., and may be of substantially any diameter dependent upon the quantity of glycerides or acids to be passed therethrough. The height of the column preferably is approximately within the range of 30 to 50 feet. However, these limits may be substantially exceeded, if so desired. It also is provided with a cover or jacket II, which, as shown, may be formed in separate sections, such as I2, I3 and I4, and may be of substantially any number dependent upon the gradation of temperature within the column which it may be desired to maintain The sections may be supplied with heat exchange medium, such as water or the like through inlets I6 and outlets Il. The inlets may be connected to separate sources of heat exchange medium at different temperatures, or if preferred they may all be connected to a single source. Also, as shown in the drawing, the outlet conduit may be connected bya conduit I8 with the inlet conduit of the adjacent section. The various conduits are supplied with valves I3, which 'may be opened or closed to admit of the circulation of the heat exchange medium through each section of the jacket individually or to cause the fluid to flow from the outlet of one section to the inlet of the adjacent section asmay be desired.

Glyceride oil or free acids of glyoeride oils may be stored in a container 2|, which, also, may be provided with a jacket 22 by means of which it may be maintained at any desired temperature. Hydrocarbon, such as naphtha. may be added through conduit 22a. Oil from the container iiows through conduit 23 and is forced by suitable pump 24 into an intermediate portion of the column I0, preferably at a distance of about 12 feet from the bottom of the column.

Solvent for the extraction may be stored in a container 23 and is fed through conduit 26 to a pump 21, connected to conduit 28 in a heater jacket `29, having at one extremity an inlet 3| for heated fluid such as water and at the opposite extremity an outlet 32 for the waste iiuid. In some instances it may be desirable to add water or other iiuid at least partially miscible with the solvent, but immiscible with the materialto be refined, in order to reduce miscibility thereof in the solvent. Such addition may be made through conduit 32a. 'Ihe upper extremity of conduit 28 discharges into the upper extremity of the column I at a short distance from the top thereof. Inert gas such as CO3 may be supplied to blanket the solvent through conduit 32h.

It will be apparent that by. reason of the difference in s peciilc gravity ofi the solvent and the glyceride oil or the acids derived therefrom the two liquids will tend to ow countercurrently with respect to each other. Assuming that the solvent is the heavier component it will descend while the undissolved oil will rise. Therefore, in a zone 33 extending approximately from the inlet for the solvent down some distance below the inlet for the glyceride oil or the acids, there will be a mixture of countercurrently owing components. Also, the oil will be carried by the solvent a certain distance below the oil inlet. In the zone of countercurrent :dow of selective solvent and oil or acid it will be apparent that there is very intimate contact, and the selective solvent gradually extracts a fraction which is rich in the more soluble component, such as the more unsaturated or actively unsaturated glycerides and acids, or the glycerides or acids which are more soluble by reason of differences and chain length in the molecule. The less soluble components of the oil do not dissolve in the solvent, at least not completely but do tend to take up a certain amount of the solvent. In a zone near or slightly above the inlet` for the conduit 28 the less soluble component or raffinate will form a layer or body 3B of insoluble glycerlde oil, or oil acid, which is saturated or substantially saturated with solvent and may be drawn of! through a conduit 31, that leads to suitable apparatus (to be later described) for the separation of the solvent dissolved therein. Inert gas is admitted through conduit 31a to blanket the rafnnate.

'I'he undissolved solvent with the extract phase therein ultimately separates out in the bottom of the column as a distinct layer or fraction 33, which may be drawn off through a conduit 4I, that extends upwardly a suillcient height to admit of hydrostatically balancing of the liquid l therein against the liquid contained in the extraction column Il.

Since the solvent and the oils are of diiferent specinc gravity, and since under varying conditions there will be a tendency for the relative .amounts thereof in the column I0 to vary somewhat, it is desirable to provide at the upper extremity of the conduit Il a section 42 which can be elevated kor lowered'to accommodate for the variations, thus making it possible to assure that the various strata in the column ill are approximately at the desired levels. I'he upper extremity of the adjustable section I2 is provided with a head 43, in which the pressure may be atmospheric. This head is iilled with inert gas through conduit 43a.

The solvent charged with extract discharges through this head to a conduit Il leading to the upper extremity of a flash vaporizing column I8, provided with a Jacket 41 to which steam at a pressure of 20 or 30 pounds per square inch or other heat exchange medium may be admitted through conduit 43 and from which spent medium is discharged through conduit 43. 'Ihe oil is delivered into column I6 as a shower or spray that falls into a spray trap Il in which the droplets of separated oil, largely freed of the solvent. are collected. The column 43 preferably is maintained under partial vacuum, e. g. under a pressure of or 300 m. m. Vaporization of' solvent.

in the column is almost instantaneous. The soivent vapors pass oi! from the trap through conduit 52 to a condenser 33, which in turn discharges through conduit 5l and pump Il back to the solvent container 25.

The extract separated from the vaporized solvent in the trap is discharged through conduit 51 to a surge tank 58, having inlet 59 for inert gas. From the tank, it, or any suitable portion thereof, is discharged through conduit BI to stripping apparatus (to be described later) .for removal of the last traces of the solvent contained therein. A portion of the extract with the small amount of solvent therein is discharged through conduit 62 to pump 63, which forces it through conduits 64 back into the column I0 at a point preferably below the feed oil inlet, but slightly above the upper limit of the separated solvent phase in the lower portion of the container. The concentration of the more soluble component is thus increased in a zone adjacent to solvent-extract layer and this results in the separation of more of the less soluble component from the oil so that ultimately an extract is obtained, which is richer in the more soluble component and poorer in the less soluble component, than would otherwise be obtained. Substantially any ratio of the extract, for example 10 to 90% of the extract may be recycled.'

As previously stated the inlet for the recycled oil is slightly above the level of the separated solvent and preferably it is at such distance below the level of the inlet for the oil that the recycled oil, as it passes upwardly through the solvent, will reach approximately the same composition as the feed oil from the container 22. Assuming that furfural is employed as the selective solvent the distance between the inlets of the feed oil and the recycled oil may be approximately 12 feet. The distance between the inlets for the feed oil and the solvent may vary over a substantial range, but preferably is about 15 to 35 feet.

If preferred, separation of the extract from the solvent may be effected by addition of water, e. g. 3 to 15% of water or other non-solvent, at a temperature below that of miscibility. The

`vaporizer I6 may then be eliminated or may be by-passed by conduit 65 interconnecting conduit 44 and conduit 51. Separation of the extract may be effected in `the latter by addition of water through conduit 65a. Where wet furfural is used, the oil may be simply cooled in order to effect stripping of solvent without addition of more `water.

The apparatus for removing the dissolved solvent from the railinate includes a vaporizer column 66 into the upper extremity of which the conduit 31 discharges the raffinate as a spray. The column is provided with a heating jacket 61, which is supplied with steam or other heated uid by means of conduit 68 and the spent fluid is discharged from the jacket through conduit 69. The pressure within the column 66 like that in column 46 is subatmospheric-e. g., about 100 to 300 m.m. of mercury and evaporation of the most of the solvent is almost instantaneous. At its lower extremity the column discharges into a conventional spray trap 1I, in which the droplets of ramnate from which much of the dissolved solvent has been evaporated are collected.

The solvent freed of railinate and in vapor state is discharged through a conduit 12., to a line 13 leading to a condenser and source of vacuum (not shown). The raillnate, separated from the vapors in the trap 1| and still containing some solvent, is discharged through conduit 14 into the upper extremity of a stripping column 16, which column is provided with a jacket 11 supplied with steam or other heated uid through conduits 18, having a connection to a line 19. Where steam is employed-the pressure is preferably about 50 lbs. per square inch corresponding to about 280 F. The spent fiuid is discharged from the bottomof the jacket through conduit 8l.

Column 16 preferably is packed' with an inert material such as Raschig rings, Berl saddles or other packing material designed to check the descent of the oil and to cause it to be spread out into thin films presenting large surfaces. Steam or other distilling medium is introduced at the bottom of the column through conduit 82 and passes upwardly through the packing in such manner as intimately to contact with the surface of the oil and thus to carry away any solvent dissolved therein. The steam passes out of the column more or less completely charged with solvent through conduit 83 and is discharged into the line 12. The rafnate oil now freed of solvent is discharged through conduit 84 at the bottom of the column and is passed to storage or is passed on for further treatment, for example, for an additional extraction in further stages of apparatus. Such stages obviously may assume substantially the form of the apparatus herein disclosed and by such treatment it is possible to remove an additional fraction or fractions of more soluble component from the ramnate.

The conduit 6| carrying the more soluble or extract components of the glyceride oil or the acids thereof, namely the more unsaturated components, is discharged into a second stripping column 86 substantially corresponding in construction to the column 16 and having a jacket 81 for steam or other uid as previously described in connection with the column 16. The column is also packed as indicated at 88 and is supplied with steam through conduit 89. Steam discharged with solvent discharges from the upper extremity of the column through conduit 9|, which also discharges into the vapor line 13 and passes on to suitable apparatus for separation of the solvent from the water vapors. The

component of the oil which initially is dissolved in the solvent and which is liberated in the column 86 is discharged from the bottom of the latter through a conduit 92, is either passed to storage or is subjected to further treatment, for example, to further fractionation in additional stages of apparatus in order more completely to separate out any saturated or less soluble components which may be carried therein. In this way a fraction which is very rich in unsaturates or other component, which is selectively soluble in the solvent employed, may be obtained.

The fractions as obtained in the present process are susceptible of very broad application. For example, it is possible to separate soya bean oil into a relatively unsaturated fraction which has good drying properties and may be employed as a substitute for more expensive linseed oil. At the same time there is obtained a rafnate fraction which is relatively low in unsaturates and this fraction is particularly useful in food products such as shortenings, margarine, salad oils, or in soaps and the like. Heretofore the use of soya bean oil in food products has been somewhat restricted by reason of the fact that it tended to become rancid, by reason of certain chemical reactions occurring therein. It has been found that soya bean oil fractionated by the process as herein disclosed is greatly improved in this respect. It will, of course, be apparent that the oil is improved as a food product for certain purposes, because the more highly saturated components have substantial higher melting points than the less saturated components. Therefore, it is possible to separate out a fraction having higher melting points than the initial oil,` which fraction is Well adapted for use in shortenings and the like. Of course the saturated ranate fraction is well adapted for use in soaps in which the unsaturated are to be avoided. In soap products development of rancidity by reason of chemical change is also objectionable and since the raillnate obtained by the present pr'ocess exhibits lesstendency to become rancid it is particularly useful therein.

Either the ralnate or the extracted oils or the free acids of the oils herein disclosed may be' subjected to hydrogenation by appropriate processes. For example, they may be confined in an autoclave under pressure and hydrogenated to a suitable degree in the presence of a catalyst of hydrogenation, such as finely-divided nickel or the like.

The extracted oils as obtained from linseed, soya bean, marine oils, perilla oil and others containing substantial amounts of glycerides susceptible of air drying are excellently adapted for use as drying oils in the fabrication of paints and varnishes. By application of the extraction process extracted oil having good drying properties and suiliciently free of objectionable matter, such as free acids, anti-oxidants break-producing constituents and the like can be obtained without subjecting the oil to severe treatment with acid or alkali. nishes the conventional pigments, colors, thinners and the like are added as with conventional drying oils. For example, titaniumv oxide, litho-V pone and other pigments may be added in amounts of 5 to 60%. Turpentine or any other volatile thinner may be also added in an amount of 10 to 25%.

The forms of the invention herein disclosed In the fabrication of paints and var-l are merely representative. Numerous modifica# tions can be made therein without departure from spirit of the invention or the scope of the appended'claims.

What I claim is:

1. A process of separating into fractions a material selected from a class consisting of glyceride oils and free fatty acids derived from such oils. which material comprises components, one of which is of relatively high polar moment and. another of which is of relatively low polar mo- 2. A process as dened in claim 1 in which the solvent is further admixed with a hydrocarbon which is immiscible therewith, but is miscible with the material to be fractionated.

3. A process as denned in claim l in which the temperature at which the separation .of the phases is eil'ected is about to 50 C. below that of cnplete miscihility of the system.

4.Aprocessasdeiinedinclaim1inwhichthe polar solvent is acetone.

5. Aprocess as denned inclaim l in which the material treated is a free fatty acid.

6. Aprocessasdefinedinclaimlinwhichthe material treated is a glyceride oil.

'1.l A process as deilned in claim 1 in which the solvent is furiural.

8. A process as deilned in claiml in which the solvent is acetone.

9. A process as defined in claim 1 in which the solvent is selected from a group consisting of the compounds in Tables A and B.

10. A process as defined in claim 1 in which the material treated is from a class consisting of soya bean oil, cottonseed oil. linseed oil and coconut oil.

11. Aproeess as deilned inclaim 1 in which the component of the oil of high polar moment is relatively highly unsaturated andthe component oftiw polar moment is more completely satura 12. A process as defined in claim 1 in which the component ofthe oil of high polar moment oomprises a glyceride of an acid of relatively short.

chain length and the component of low polar moment comprises a glyceride of an acid of rela.

tively long chain length.

JOHN D. JENKINS. 

